TUCSON, Ariz. -- Arizona found its defense just in time to earn a day off.

Jumping into passing lanes and blocking all paths to the basket, No. 18 Arizona turned turnovers into easy points on its way to a 73-58 rout of Arizona State on Saturday that earned the Wildcats a first-round bye in next week's Pac-12 tournament.

"We just needed to get back to our defense," senior Solomon Hill said after his final home game for Arizona. "It was good to really get after them and I think guys are really revved up from it."

Dominating the first half of the season, Arizona's defense had faltered over the last month or so, sending the Wildcats into a slide that put them in danger of having to play in the opening round of the conference tournament.

The Wildcats (24-6, 12-6 Pac-12) got their defensive groove back against Arizona State, forcing 17 turnovers that led to 21 points and cutting off ASU point guard Jahii Carson's lanes to the basket.

Nick Johnson helped Arizona answer a big second-half run by Arizona State by scoring seven of his 17 points as the Wildcats pulled away. Kevin Parrom had 13 points in his final game at McKale Center and Hill added 12 with four assists and three steals.

Freshman Kaleb Tarczewski gave Arizona a nice lift with one of his most aggressive games of the season, finishing with nine points and eight rebounds.

The Wildcats also had 12 more rebounds, including a 13-3 advantage on the offensive end, to wrap up the fourth seed for the Pac-12 tournament in Las Vegas.

"Today's margin of victory was because of our defense," Arizona coach Sean Miller said. "We had the stops and we kept the game moving at the rim."

Arizona State (20-11, 9-9) shot better than Arizona (46 to 44 percent), got a nice bounce-back game from Carrick Felix and trimmed a 15-point deficit to five midway through the second half to deflate the sold-out McKale Center crowd.

The Sun Devils just let the ball slip through their hands too many times and struggled to match up with the athletic Wildcats, likely forcing them into a four-wins-in-four-days run at the Pac-12 tournament if they want to make the NCAAs.

Felix scored 22 points after having a miserable game against Arizona in January and Carson added 15, but had six turnovers for the Sun Devils.

The 224th installment of this desert rivalry had the added specter of both teams in need of a big win.

After opening 12-0 in nonconference play, Arizona has played inconsistently during the Pac-12 season, particularly on the defensive end. Following a sweep by the two Southern California schools, the Wildcats needed to beat the Sun Devils to assure themselves of earning a coveted bye for the first round of the conference tournament.

Arizona State has taken a more precipitous fall since opening 11-2 in nonconference action, losing five of its previous seven games, including three straight. The Sun Devils were going to play in the opening round of the Pac-12 tournament no matter what and likely will need to win the title to get into the NCAA tournament.

Arizona State managed to keep it close the first time around against Arizona on Jan. 19 in Tempe, but allowed the Wildcats to pull away over the final 10 minutes after Carson got into foul trouble. Felix struggled in that game, scoring five points on 1-of-8 shooting -- seven of those 3s -- with seven turnovers.

Both were good early against Arizona in the rematch, combining for 19 of Arizona State's 25 first-half points.

What hurt the Sun Devils in the opening half were turnovers. They had nine -- four by Carson -- leading to 12 points for Arizona, which rode its defensive effort to a 40-25 halftime lead.

"The biggest thing for our team is defense," Johnson said. "I'm glad we were able to get that back."

Johnson brought a roar from the crowd by turning an early turnover into a fast-break dunk in the second half, but those turned to boos after some calls went against the Wildcats and the Sun Devils scored six straight points.

Arizona State kept the momentum going, using a 15-4 run to pull to 48-43 on Jonathan Gilling's 3-pointer from the corner.

"I was really proud of the way our guys battled back," Sendek said.

Arizona wouldn't let the Sun Devils any closer.

Johnson dropped in a 3-pointer to start a solo 7-0 run that put Arizona up 57-45, and Hill brought the crowd to its feet with a steal and a dunk for a three-point play in a 14-3 run that turned the game into a runaway and gave the Wildcats the day off they wanted.